<html>
	<head>
		<title></title>
		<style>
			#box{
				width:300px;
				height: 300px;
				
				background-color: red;		/*背景色*/
				color: white;				/*文字颜色*/
				font-size: 30px;			/*文字大小*/
				font-weight: bold;			/*文字加粗*/
			}
			
			#line{
				/*行内元素的宽度和高度不起作用*/
				width: 300px;
				height: 300px;
				
				background: blue;
				color: white;
			}
		</style>
	</head>
	<body>
		<div id="box">你好</div>
		<span id="line">株洲空气真好</span>
		
	</body>
</html>